HBase Replication Metrics

The following metrics are exposed at the global Region Server level and at the peer level (since HBase 0.95):

Metric	Description
`source.sizeOfLogQueue`	Number of WALs to process (excludes the one which is being processed) at the replication source.
`source.shippedOps`	Number of of mutations shipped.
`source.logEditsRead`	Number of mutations read from WALs at the replication source.
`source.ageOfLastShippedOp`	Age of last batch shipped by the replication source.